Methods, modems and computer program products for identification of a modem type and adjustment of a communication configuration based on modem type
    1.
    发明授权
    Methods, modems and computer program products for identification of a modem type and adjustment of a communication configuration based on modem type 有权
    用于识别调制解调器类型的调制解调器和计算机程序产品以及基于调制解调器类型的通信配置的调整

    公开(公告)号:US06757325B1

    公开(公告)日:2004-06-29

    申请号:US09430698

    申请日:1999-10-29

    IPC分类号: H04L516

    CPC分类号: H04L25/4927

    摘要: Methods, modems and computer program products for detecting whether a remote modem is of a particular design type and for adjusting the communication configuration for a communication session based on a type of the remote modem. The modem type is recognized based on a knowledge that the modem design of certain manufacturers has a unique associated data pattern contained within the startup communication sequence which is not specified by the protocol but which can be demodulated and detected to thereby recognize that the remote modem is a particular manufacturer's design type. Based on knowledge of the characteristics of the remote modem design, various steps are taken which may improve performance of the communication connection in light of the particular modem design's characteristics. For example, a different Total Harmonic Distortion (THD) threshold may be used for falling back to V.34 communications when the remote modem design only supports up to 2 look ahead for spectrum shaping.

    摘要翻译: 用于检测远程调制解调器是否是特定设计类型的方法,调制解调器和计算机程序产品,以及用于基于远程调制解调器的类型来调整通信会话的通信配置。 基于知道某些制造商的调制解调器设计具有包含在启动通信序列内的唯一关联数据模式的知识,可以识别调制解调器类型,该数据模式不是由协议规定的,而是可以被解调和检测,从而识别远程调制解调器 特定制造商的设计类型。 基于对远程调制解调器设计的特征的了解,采取了各种步骤,可以根据特定的调制解调器设计的特性改善通信连接的性能。 例如,当远程调制解调器设计仅支持最多2个前进用于频谱整形时,可以使用不同的总谐波失真(THD)阈值来回退到V.34通信。

    MODEMS, METHODS, AND COMPUTER PROGRAM PRODUCTS FOR SELECTING AN OPTIMUM DATA RATE USING ERROR SIGNALS REPRESENTING THE DIFFERENCE BETWEEN THE OUTPUT OF AN EQUALIZER AND THE OUTPUT OF A SLICER OR DETECTOR
    2.
    发明授权
    MODEMS, METHODS, AND COMPUTER PROGRAM PRODUCTS FOR SELECTING AN OPTIMUM DATA RATE USING ERROR SIGNALS REPRESENTING THE DIFFERENCE BETWEEN THE OUTPUT OF AN EQUALIZER AND THE OUTPUT OF A SLICER OR DETECTOR 失效
    使用错误信号选择最佳数据速率的方式,方法和计算机程序产品,表示均衡器的输出与切换器或检测器的输出之间的差异

    公开(公告)号:US06665336B2

    公开(公告)日:2003-12-16

    申请号:US10428357

    申请日:2003-05-02

    IPC分类号: H04B1700

    摘要: Modems, methods, and computer program products select a data rate based on error signals in a modem. In an illustrative embodiment, error signals representing the difference between an output of an equalizer and an output of a detector are accumulated and an average error value is computed therefrom. A signal to noise ratio is determined using the average error value. The signal to noise ratio is then used to select a data rate. In another illustrative embodiment, the mean squared error at the output of the equalizer is determined and then used, along with the probability of error in correctly detecting a symbol, to select a data rate. Incorrect decisions in detecting received data symbols can cause a catastrophic failure in a decision feedback equalizer used in a modem receiver as errors are repeatedly fed back causing the tap coefficients for the equalizer filters to be shifted from their normal operating values. By adjusting the data rate in accordance with the error signals generated in a modem receiver, the decision feedback equalizer can operate with greater stability as the data rate can be reduced in response to increased noise conditions.

    摘要翻译: 调制解调器,方法和计算机程序产品根据调制解调器中的错误信号选择数据速率。 在说明性实施例中,代表均衡器的输出和检测器的输出之间的差的误差信号被累加,并且从其计算出平均误差值。 使用平均误差值确定信噪比。 然后使用信噪比来选择数据速率。 在另一说明性实施例中,确定均衡器的输出处的均方误差,然后与正确检测符号的误差概率一起使用以选择数据速率。 检测接收到的数据符号时的不正确决定可能导致在调制解调器接收机中使用的判决反馈均衡器中的灾难性故障,因为错误被反复反馈,导致均衡器滤波器的抽头系数从其正常操作值偏移。 通过根据在调制解调器接收机中产生的误差信号来调整数据速率,当响应于增加的噪声条件可以减小数据速率时,判决反馈均衡器可以更稳定地工作。

    Systems, methods and computer program products for identifying digital impairments in modem signals
    3.
    发明授权
    Systems, methods and computer program products for identifying digital impairments in modem signals 失效
    用于识别调制解调器信号数字损伤的系统,方法和计算机程序产品

    公开(公告)号:US06650657B1

    公开(公告)日:2003-11-18

    申请号:US09429859

    申请日:1999-10-29

    IPC分类号: H04J324

    CPC分类号: H04J3/125

    摘要: Robbed Bit Signaling (RBS) and PAD digital impairments in sets of Digital Impairment Learning (DIL) signals that are repeatedly transmitted from a server modem to a client modem during DIL intervals are identified by identifying a PAD level for the sets of DIL signals in the DIL intervals and then identifying an RBS type for individual sets of DIL signals based upon the PAD levels so identified. The PAD level may be identified using model DIL signals that correspond to PAD levels that are not subject to RBS. The RBS type may be identified using model DIL signals that correspond to multiple RBS types that are subject to the identified PAD level. More specifically, one of the DIL intervals that contains DIL signals that are not subject to RBS is identified. A PAD level for the DIL signals in the one of the DIL intervals so identified then is determined. The PAD level that was determined is applied to the DIL signals in remaining ones of the DIL intervals, to identify an RBS for the DIL signals in the remaining ones of the DIL intervals.

    摘要翻译: 通过在DIL间隔期间从服务器调制解调器重复发送到客户端调制解调器的数字损伤学习(DIL)信号中的Robbed位信令(RBS)和PAD数字损伤被识别为DIL信号组中的PAD电平 DIL间隔,然后基于所识别的PAD水平识别用于各组DIL信号的RBS类型。 可以使用对应于不受RBS的PAD电平的模型DIL信号来识别PAD电平。 可以使用对应于经受所识别的PAD电平的多个RBS类型的模型DIL信号来识别RBS类型。 更具体地,识别包含不受RBS的DIL信号的DIL间隔之一。 确定如此识别的DIL间隔之一中的DIL信号的PAD电平。 将确定的PAD电平应用于DIL间隔中剩余的DIL信号,以识别DIL间隔中剩余的DIL信号中的DBS信号的RBS。

    Receivers, methods, and computer program products for an analog modem that receives data signals from a digital modem
    5.
    发明授权
    Receivers, methods, and computer program products for an analog modem that receives data signals from a digital modem 失效
    用于从数字调制解调器接收数据信号的模拟调制解调器的接收器,方法和计算机程序产品

    公开(公告)号:US07003030B2

    公开(公告)日:2006-02-21

    申请号:US10635194

    申请日:2003-08-06

    IPC分类号: H03K5/159

    摘要: Receivers, methods, and computer program products can be used to demodulate a data signal transmitted from a digital source, which has a network sampling rate that is synchronized with a network clock. In an illustrative embodiment, a receiver includes a two-stage interpolator that receives digital samples of the data signal as an input and produces an interpolated digital sample stream to be filtered by an adaptive fractionally spaced decision feedback equalizer. The digital samples received in the interpolator are synchronized with a local clock; however, the interpolated sample stream is synchronized with the network clock. A slicer generates symbols for the samples output from the decision feedback equalizer by comparing the samples with a reference signaling alphabet. The receiver can be used in a V.90 client modem to demodulate pulse code modulated (PCM) data transmitted as pulse amplitude modulated (PAM) signals from a digital network. In addition, the receiver is compatible with legacy analog modem front ends and transmitters. The two-stage interpolator allows the timing synchronization to be performed with extremely fine granularity, which can be useful in PCM modems that typically require relatively high signal to noise ratios.

    摘要翻译: 接收器,方法和计算机程序产品可用于解调从具有与网络时钟同步的网络采样速率的数字源发送的数据信号。 在说明性实施例中,接收机包括二阶插值器,其接收作为输入的数据信号的数字样本,并产生经过自适应分数间隔的判决反馈均衡器滤波的内插数字样本流。 在内插器中接收的数字样本与本地时钟同步; 然而,插值的采样流与网络时钟同步。 切片器通过将样本与参考信号字母表进行比较来生成从判决反馈均衡器输出的样本的符号。 接收机可用于V.90客户端调制解调器中,以解调从数字网络传输的脉冲编码调制(PCM)数据作为脉冲幅度调制(PAM)信号。 此外,接收机与传统模拟调制解调器前端和发射机兼容。 两级内插器允许以非常精细的粒度执行定时同步,这在通常需要相对较高的信噪比的PCM调制解调器中是有用的。

    Systems, methods and computer program products for filtering glitches from measured values in a sequence of code points
    6.
    发明授权
    Systems, methods and computer program products for filtering glitches from measured values in a sequence of code points 失效
    用于从代码点序列中的测量值过滤毛刺的系统,方法和计算机程序产品

    公开(公告)号:US06823017B1

    公开(公告)日:2004-11-23

    申请号:US09432023

    申请日:1999-10-29

    IPC分类号: H04B1406

    CPC分类号: H04B14/046

    摘要: Glitch filters, methods, and computer program products that utilize the generally monotonically increasing characteristics of the expected levels of code points to detect and remove noise spikes by replacing values in the code point sequence with new values based on the code points around a suspect value are provided. Measured values associated with two code points in the sequence of code points which are immediately higher in the sequence of code points than a code point of interest are evaluated so as to select a larger value of the two code points in the sequence as a first reference value. The first reference value is compared with a measured value associated with a code point in the sequence of code points immediately lower than the code point of interest to determine if the first reference value is smaller than the measured value associated with the code point in the sequence of code points immediately lower than the code point of interest. The smaller of the first reference value and the measured value associated with a code point in the sequence of code points immediately lower than the code point of interest is then selected so as to provide a first replacement value. The measured value associated with the code point of interest is then replaced with the first replacement value if the first reference value is smaller than the measured value associated with the code point of interest.

    摘要翻译: 毛刺滤波器,方法和计算机程序产品利用通常单调增加的代码点级别的特征来检测和消除噪声尖峰,通过使用基于可疑值周围的代码点的新值替换代码点序列中的值, 提供。 评估与编码点序列中的代码点比代码点高的代码点序列中的两个代码点相关联的测量值,以选择序列中的两个代码点的较大值作为第一参考 值。 将第一参考值与与紧接着感兴趣码点的代码点序列中的代码点相关联的测量值进行比较,以确定第一参考值是否小于与序列中的代码点相关联的测量值 的代码点立即低于感兴趣的代码点。 然后选择第一参考值和与紧接着感兴趣的代码点的代码点序列中的代码点相关联的测量值中的较小者,以提供第一替换值。 如果第一参考值小于与感兴趣的代码点相关联的测量值,则与感兴趣的代码点相关联的测量值被替换为第一替换值。

    Modems having a dual power mode capability and methods of operating same
    7.
    发明授权
    Modems having a dual power mode capability and methods of operating same 失效
    具有双功率模式能力的调制解调器和操作相同的方法

    公开(公告)号:US06792040B1

    公开(公告)日:2004-09-14

    申请号:US09430678

    申请日:1999-10-29

    IPC分类号: H04L516

    摘要: Modems, methods, and computer program products provide a dual power mode capability in which a maximum power limit is determined for a received signal and, based on that determination, at least one modem operational parameter is adjusted and/or digital impairment learning (DIL) sequence is selected. Adjustments made to the operational parameters may allow a modem to operate in a high power mode to achieve a higher downstream data rate. The higher downstream data rate may be attributed to an improved SNR resulting from an increase in data transmission power. Moreover, the modem may also operate in a normal power mode where the operational parameters may be set to maximize the client modem receiver's dynamic range. By selecting the DIL sequence based on the power limit, a DIL signal containing symbols having power levels within the power limit may be selected.

    摘要翻译: 调制解调器,方法和计算机程序产品提供双功率模式能力,其中为接收到的信号确定最大功率限制,并且基于该确定,调整至少一个调制解调器操作参数和/或数字损伤学习(DIL) 选择序列。 对操作参数进行的调整可允许调制解调器以高功率模式工作,以实现更高的下行数据速率。 较高的下行数据速率可能归因于由于数据传输功率的增加而导致的改善的SNR。 此外,调制解调器还可以以正常功率模式操作,其中可以设置操作参数以最大化客户端调制解调器接收机的动态范围。 通过基于功率限制选择DIL序列,可以选择包含具有功率限制内的功率电平的符号的DIL信号。